JP4196779B2 - Process for producing conductive composition for electrophotographic equipment - Google Patents

Description

  The present invention relates to a method for producing a conductive composition for an electrophotographic apparatus, and more specifically, a developing roll, a charging roll, a transfer roll, a toner supply roll, a charge eliminating roll, a paper feeding roll, a transport roll, a cleaning roll, a developing blade, The present invention relates to a method for producing a conductive composition for an electrophotographic apparatus used for a member for an electrophotographic apparatus such as a charging blade, a cleaning blade, or a transfer belt.

  In general, as a method for controlling electrical resistance in the electrophotographic field, (1) a method of dispersing an electronic conductive agent such as carbon black in a matrix polymer, or (2) an ionic conductive agent such as a quaternary ammonium salt, Examples thereof include a method of dispersing in a matrix polymer.

  In the method (1), since the electron conductive agent particles such as carbon black are dispersed in the matrix polymer and the conduction is controlled by the conduction of electrons, the dispersion of the electron conductive agent particles is not affected by temperature and humidity. Uniform conductivity control is difficult due to the influence of the state, the influence of the material flow in the molding process, the influence of the coating and drying state, and the like.

  On the other hand, in the method (2), since the ionic conductive agent is dissolved in the matrix polymer, uniform conductivity control is possible, but even if it can be made conductive, it is easily affected by temperature and humidity. There is a tendency that the electric resistance tends to increase with energization and the image quality is not stable. In addition, there is a problem that a matrix polymer capable of exhibiting an effect is restricted from the viewpoint of compatibility with an ionic conductive agent.

In order to solve these problems, a method for controlling electric resistance using carbon nanotubes instead of an electron conductive agent such as carbon black or an ionic conductive agent such as quaternary ammonium salt has been proposed. For example, in a contact-type charger of an image forming apparatus such as an electrophotographic copying machine, printer, facsimile, etc., there are resin layers arranged discretely on the surface in contact with the photoreceptor, and the carbon nanotubes are formed by this resin layer. Has been proposed (for example, see Patent Document 1).
JP 2002-132016 A

  However, the contact charger described in Patent Document 1 has a structure in which carbon nanotubes are fixed and held on the surface of a resin layer composed of a thermoplastic polymer resin layer or the like. There was a problem that the dispersibility of the nanotubes was inferior and the variation in electrical resistance was large.

The present invention has been made in view of such circumstances, excellent dispersibility of carbon nanotubes, and variation in the electric resistance is small, and its object to provide a process for preparing an electrophotographic apparatus for conductive composition To do.

In order to achieve the above object, the method for producing a conductive composition for an electrophotographic apparatus according to the present invention comprises 0.2 to 3 parts by weight of the following (B) with respect to 100 parts by weight of the following (A): (a) below in at below the (B) was pre-dispersed, after it Shin loosen the (B) is formed by a number agglomerated aggregates were predispersed (a) and (B) It is configured to include a kneading step.
(A) A liquid polymer having a viscosity of 10,000 to 80,000 mPa · s (25 ° C.) .
(B) Carbon nanotubes having a diameter of 1 to 50 nm .

That is, the inventors is excellent in dispersibility of carbon nanotubes, and variation in the electric resistance is small, to obtain the electrophotographic apparatus electrically conductive composition, conducted intensive research. And when research was continued about the control method of the electrical resistance in the contact-type charger described in Patent Document 1, in this contact-type charger, the surface of the resin layer composed of a thermoplastic polymer resin layer or the like is formed. The carbon nanotubes are merely fixed and held, and the carbon nanotubes are not kneaded in the resin layer, so that the dispersibility of the carbon nanotubes is inferior and the electric resistance varies greatly. Therefore, was further continued research in advance in the liquid polymer, by pre-dispersing carbon nanotubes, after stretching loosen aggregates of carbon nanotubes (mass), a liquid polymer and carbon nanotubes It has been found that when kneaded, a conductive composition for an electrophotographic apparatus having excellent dispersibility of carbon nanotubes in a liquid polymer and small variation in electrical resistance can be prepared, and the present invention has been achieved.

According to method for an electrophotographic apparatus electroconductive composition of the present invention, in advance, a liquid polymer, by pre-dispersing carbon nanotubes, after stretching loosen aggregates of carbon nanotubes (mass), liquid Since the polymer and the carbon nanotube are kneaded, it is possible to produce a conductive composition for an electrophotographic apparatus that is excellent in dispersibility of the carbon nanotube in the liquid polymer and has a small variation in electric resistance.

  Next, embodiments of the present invention will be described in detail.

The method for producing a conductive composition for an electrophotographic apparatus according to the present invention comprises an aggregate formed by pre-dispersing carbon nanotubes (B component) in a liquid polymer (A component) and aggregating many of the carbon nanotubes (B component). after if Shin loosen the includes a step of kneading the pre-dispersed the liquid polymer (a component) and carbon nanotubes (B component).

  Examples of the liquid polymer (component A) include liquid silicone rubber, liquid polyoxyalkylene rubber, liquid polyisobutylene rubber, liquid butadiene rubber (BR), liquid isoprene rubber, liquid styrene-butadiene rubber, liquid ethylene-propylene- Examples thereof include diene terpolymer rubber (EPDM) and ultraviolet crosslinking binder. These may be used alone or in combination of two or more. Among these, liquid silicone rubber, liquid polyoxyalkylene rubber, and liquid butadiene rubber are preferably used because they can be crosslinked for a short time.

  In the present invention, the liquid rubber refers to rubber that is liquid at room temperature (about 20 ° C.) and that is plastically deformed by its own weight. In addition, in the two or more kinds of blended products, even if one or more of the blended products is not liquid, the blended product may be liquid.

  Examples of the ultraviolet crosslinking binder include oligomers such as epoxy acrylate, urethane acrylate, polyester acrylate, and acrylic acrylate having a molecular weight of 500 to 5500. These may be used alone or in combination of two or more.

Next, carbon nanotubes (component B) are used together with the liquid polymer (component A).

Diameter of the carbon nanotube (B component) is. 1 to 50 nm, preferably not more diameter is 25nm or less. That is, when the diameter exceeds 50 nm, it is difficult to control the conductivity with a small amount of addition, because the addition of a large amount is likely leaving adverse effect on the physical properties.

The mixing ratio of the carbon nanotube (component B) is in the range of 0.2 to 3 parts with respect to 100 parts by weight (hereinafter abbreviated as “part”) of the liquid polymer (component A). That is, when the B component is less than 0.2 part, will not be able to impart electrical conductivity and conversely B component exceeds 3 parts, adverse effects on physical properties (sag, increase in hardness) is de Luca et al It is. Thus, in this invention, since the compounding ratio of the said carbon nanotube (B component) can be made small, transparency appears and ultraviolet curing is also possible.

The process for producing a conductive composition for electrophotographic equipment of the present invention is performed, for example, as follows. That is, carbon nanotubes (component B) are blended in the liquid polymer (component A) and predispersed by a method such as bead milling, ultrasonic wave, stirring, grinding or the like. In this case, liquid polymer (A component), viscosity is used those 10,000~ 80,000mPa · s (25 ℃) , preferably of less than 20,000mPa · s (25 ℃). That is, when the viscosity of the liquid polymer (component A) exceeds 80,000 mPa · s (25 ° C.), the component B tends to disperse in an aggregated state in the component A.

Next, the liquid polymer (component A) and the carbon nanotube (component B) are kneaded using a three-roll, kneader or the like. In this kneading step, the viscosity of the mixture is preferably set to 50,000 mPa · s (25 ° C.) or more, particularly preferably 100,000 mPa · s (25 ° C.) or more. That is, if the viscosity of the mixture during the kneading step is less than 50,000 mPa · s (25 ° C.), the power of the kneader for making the B component agglomerates tend not to be transmitted to the agglomerates. is there.

In the kneading step, together with the A component and the B component, a crosslinking agent, a catalyst, a reactive diluent, a photoinitiator, a reaction retarding agent, a foam stabilizer, a filler, a plasticizer, an antiaging agent, and a dispersing agent. An antifoaming agent, a coupling agent, a flame retardant, and the like can be appropriately kneaded as necessary.

  What is necessary is just to select the said crosslinking agent according to the kind of said liquid polymer (A component), for example, hydrosilyl crosslinking agents, urea resins, such as a melamine, an epoxy hardening agent, a polyamine hardening agent, a peroxide, sulfur And silanol group-containing compounds.

  The blending ratio of the cross-linking agent is preferably in the range of 0.1 to 40 parts, particularly preferably 1 to 10 parts, with respect to 100 parts of the liquid polymer (component A). Especially, the blending ratio of the hydrosilyl crosslinking agent is preferably in the range of 0.5 to 8 parts, particularly preferably 1.5 to 3 parts, with respect to 100 parts of the liquid polymer (component A). Moreover, the blending ratio of the peroxide is preferably in the range of 1 to 10 parts, particularly preferably 2 to 5 parts, with respect to 100 parts of the liquid polymer (component A).

  Examples of the catalyst include hydrosilylation catalysts, tertiary amine catalysts, and tin-based catalysts.

  Examples of the reactive diluent include monomers such as biacetyl and acetophenone.

  The conductive composition for an electrophotographic apparatus obtained by the production method of the present invention includes, for example, a roll such as a developing roll, a charging roll, a transfer roll, a fixing roll, a toner supply roll, a static elimination roll, a paper feed roll, a transport roll, and a cleaning roll. It is used for electrophotographic equipment members such as members, developing blades, blade members such as charging blades and cleaning blades, belt members such as transfer belts and paper feed belts. Among these, it is suitably used as a base layer of a roll member such as a developing roll.

  Next, examples will be described together with comparative examples.

  Add 1 part of 1 nm diameter single-walled carbon nanotubes (manufactured by MTR, NT-5) to 100 parts of a silicone polymer (manufactured by Gelest, DMS-V33) having a viscosity of 10,000 mPa · s (25 ° C.) Used and predispersed. Next, 0.37 part of phenyl-modified methyl H siloxane (manufactured by Azmax, HPM502) as a hydrosilyl crosslinking agent and acetylene alcohol [3,5-dimethyl-1-hexyn-3-ol as a reaction retardant are added to this liquid. (DMHO)] 0.03 part and platinum catalyst (Gelest, SIP 6830.0) 0.01 part were blended and kneaded using a kneader to obtain a conductive composition (viscosity: 9850 mPa · s / 25 ° C.).

  A conductive composition was prepared in the same manner as in Example 1 except that the amount of carbon nanotube (manufactured by MTR, NT-5) was changed to 0.5 part.

  A conductive composition was prepared in the same manner as in Example 1 except that the amount of carbon nanotube (manufactured by MTR, NT-5) was changed to 0.2 part.

  A conductive composition was prepared in the same manner as in Example 1 except that the amount of carbon nanotube (manufactured by MTR, NT-5) was changed to 3 parts.

  Example 1 except that 1 part of single-walled carbon nanotube (manufactured by Shenzhen Nanotechport Co., Ltd., SWCNT-2) having a diameter of 1 nm is used instead of 1 part of single-walled carbon nanotube (manufactured by MTR, NT-5) of 1 nm in diameter In the same manner as in Example 1, a conductive composition was prepared.

  Example 1 except that 1 part of single-walled carbon nanotubes (manufactured by MTR, NT-5) having a diameter of 1 nm is replaced with 3 parts of multi-walled carbon nanotubes having a diameter of 8 nm (manufactured by Shenzhen Nanotechport, MWCNT-1). In the same manner as in Example 1, a conductive composition was prepared.

  The same as Example 1 except that 1 part of single-walled carbon nanotubes (manufactured by MTR, NT-5) having a diameter of 1 nm was used instead of 3 parts of carbon nanotubes having a diameter of 20 nm (manufactured by MTR, NT-1). Thus, a conductive composition was prepared.

  Example 1 except that 3 parts of 50 nm diameter multi-walled carbon nanotubes (manufactured by Shenzhen Nanotechport Co., Ltd., MWCNT-5) are used instead of 1 part of single-walled carbon nanotubes (manufactured by MTR, NT-5) of 1 nm diameter In the same manner as in Example 1, a conductive composition was prepared.

  To 100 parts of a silicone polymer (manufactured by Gelest, DMS-V33) having a viscosity of 10,000 mPa · s (25 ° C.), 0.5 part of a single-walled carbon nanotube having a diameter of 1 nm (manufactured by MTR, NT-5) is added, Pre-dispersed using a bead mill. Next, 0.37 part of phenyl-modified methyl H siloxane (manufactured by Azmax, HPM502) as a hydrosilyl crosslinking agent and acetylene alcohol [3,5-dimethyl-1-hexyn-3-ol as a reaction retardant are added to this liquid. (DMHO)] 0.03 part and platinum catalyst (manufactured by Gelest, SIP 6830.0) 0.01 part are blended, and these are kneaded using three rolls to form a conductive composition (viscosity: 9600 mPa · s / 25 ° C.).

  As a liquid polyoxyalkylene rubber, a single-walled carbon nanotube having a diameter of 1 nm (100 parts of polyalkylene oxide having vinyl groups at both ends (manufactured by Kaneka Chemical Co., Ltd., Silyl SAT200, viscosity: 20,000 mPa · s / 25 ° C.)) 0.5 part of MTR, NT-5) was added and predispersed using a bead mill. Next, 4.1 parts of phenyl-modified methyl H siloxane (manufactured by Azmax Co., HPM502) and 0.01 part of platinum catalyst (manufactured by Gelest Co., SIP 6830.0) are blended with the liquid material. These were kneaded using a kneader to prepare a conductive composition (viscosity: 19,500 mPa · s / 25 ° C.).

  As a liquid polyisobutylene rubber, 100 parts of isobutylene having vinyl groups at both ends (Epion EP200A, manufactured by Kaneka Chemical Co., Ltd., Mn: about 5000, viscosity: 50,000 mPa · s / 25 ° C.), monolayer carbon having a diameter of 1 nm 0.5 parts of nanotubes (manufactured by MTR, NT-5) were added and predispersed using a bead mill. Next, 7.8 parts of phenyl-modified methyl H siloxane (manufactured by Azmax, HPM502) and 0.01 part of platinum catalyst (manufactured by Gelest, SIP 6830.0) are blended with this liquid material as a hydrosilyl crosslinking agent. These were kneaded using three rolls to prepare a conductive composition (viscosity: 45,000 mPa · s / 25 ° C.).

  100 parts of liquid butadiene rubber (Kuraray, Kuraprene LIR-30) with a viscosity of 80,000 mPa · s (25 ° C.), 0.5 parts of single-walled carbon nanotubes (MTR, NT-5) with a diameter of 1 nm In addition, it was predispersed using a bead mill. Next, 2.8 parts of a hydrosilyl crosslinking agent represented by the following chemical formula (1) and acetylene alcohol [3,5-dimethyl-1-hexyn-3-ol (DMHO) as a reaction retarder are added to the liquid product. ] 0.03 part and platinum catalyst (Gelest Co., SIP 6830.0) 0.01 part were blended, and these were kneaded using three rolls to form a conductive composition (viscosity: 78,000 mPas). -S / 25 degreeC) was prepared.

  As an ultraviolet crosslinking matrix, 100 parts of an acrylic oligomer (manufactured by Shin-Nakamura Chemical Co., Ltd., NK Oligo U-201PA-60, viscosity: 15,000 mPa · s / 25 ° C.), single-walled carbon nanotubes with a diameter of 1 nm (manufactured by MTR, NT-5) 3 parts were added and predispersed using a bead mill. Next, 5 parts of a photoinitiator (Darocur 1173, manufactured by Ciba Specialty Chemicals Co., Ltd.) is blended with this liquid material, and the mixture is kneaded using three rolls to form a conductive composition (viscosity: 13,500 mPa · s). / 25 ° C.).

[Comparative Example 1]
100 parts of a silicone polymer having a viscosity of 10,000 mPa · s (25 ° C.) (manufactured by Gelest, DMS-V33), 0.5 part of single-walled carbon nanotubes having a diameter of 1 nm (manufactured by MTR, NT-5), and hydrosilyl 0.37 part of phenyl-modified methyl H siloxane (manufactured by Azmax, HPM502) as a crosslinking agent, 0.03 part of acetylene alcohol [3,5-dimethyl-1-hexyn-3-ol (DMHO)] as a reaction retarder, Then, 0.01 part of platinum catalyst (Gelest, SIP 6830.0) was blended and stirred to prepare a conductive composition (viscosity: 9,890 mPa · s / 25 ° C.).

[Comparative Example 2]
7 parts of ketjen black EC (manufactured by ketjen black international) are added to 100 parts of a silicone polymer (manufactured by Gelest, DMS-V33) having a viscosity of 10,000 mPa · s (25 ° C.), and preliminarily dispersed using a bead mill. did. Next, 0.37 parts of phenyl-modified methyl H siloxane (manufactured by Azmax, HPM502) as a hydrosilyl crosslinking agent and acetylene alcohol [3,5-dimethyl-1-hexyn-3-ol ( DMHO)] 0.03 part and platinum catalyst (Gelest, SIP 6830.0) 0.01 part are blended and kneaded using a kneader to form a conductive composition (viscosity: 45,000 mPas). -S / 25 degreeC) was prepared.

[Comparative Example 3]
100 parts of a silicone polymer (manufactured by Gelest, DMS-V33) having a viscosity of 10,000 mPa · s (25 ° C.), 15 parts of Ketjen Black EC (manufactured by Ketjen Black International), and phenyl-modified methyl as a hydrosilyl crosslinking agent 0.37 part of H siloxane (manufactured by Azmax, HPM502), 0.03 part of acetylene alcohol [3,5-dimethyl-1-hexyn-3-ol (DMHO)] as a reaction retarder, platinum catalyst (Gelest Co., Ltd.) Manufactured, SIP 6830.0) 0.01 parts, and these were stirred to prepare a conductive composition (viscosity: 89,000 mPa · s / 25 ° C.).

[Comparative Example 4]
100 parts of a silicone polymer (DMS-V33, manufactured by Gelest Co., Ltd.) having a viscosity of 10,000 mPa · s (25 ° C.), 8 parts of potassium titanate whisker (manufactured by Otsuka Chemical Co., Ltd., Dentor WK), and phenyl-modified as a hydrosilyl crosslinking agent 0.37 part of methyl H siloxane (manufactured by Azmax, HPM502), 0.03 part of acetylene alcohol [3,5-dimethyl-1-hexyn-3-ol (DMHO)] as a reaction retarder, platinum catalyst (Gelest (Commercially available, SIP 6830.0) 0.01 part was blended and stirred to prepare a conductive composition (viscosity: 58,000 mPa · s / 25 ° C.).

[Comparative Example 5]
15 parts of potassium titanate whisker (manufactured by Otsuka Chemical Co., DENTOR WK) is added to 100 parts of a silicone polymer (DMS-V33, manufactured by Gelest Co., Ltd.) having a viscosity of 10,000 mPa · s (25 ° C.) and preliminarily prepared using a bead mill. Distributed. Next, 0.37 parts of phenyl-modified methyl H siloxane (manufactured by Azmax, HPM502) as a hydrosilyl crosslinking agent and acetylene alcohol [3,5-dimethyl-1-hexyn-3-ol ( DMHO)] 0.03 part and platinum catalyst (Gelest, SIP 6830.0) 0.01 part are blended and kneaded using a kneader to form a conductive composition (viscosity: 54,000 mPas). -S / 25 degreeC) was prepared.

[Comparative Example 6]
As an ultraviolet crosslinking matrix, 100 parts of an acrylic oligomer (manufactured by Shin-Nakamura Chemical Co., Ltd., NK Oligo U-201PA-60, viscosity: 15,000 mPa · s / 25 ° C.) and carbon fiber having a diameter of 10 μm (manufactured by Idemitsu Kosan Co., Ltd., Idemitsu) 10 parts of carbon fiber MT) and 5 parts of a photoinitiator (manufactured by Ciba Specialty Chemicals Co., Ltd., Dirocure 1173) are blended and stirred to form a conductive composition (viscosity: 43,000 mPa · s / 25 ° C. ) Was prepared.

[Comparative Example 7]
Instead of 10 parts of carbon fiber, 10 parts of carbon black graft polymer (GLF21, manufactured by Nippon Shokubai Co., Ltd.) was used. Otherwise in the same manner as in Comparative Example 6, a conductive composition (viscosity: 32,000 mPa · s / 25 ° C.) was prepared.

  Using the example product and the comparative product thus obtained, each characteristic was evaluated as follows. These results are shown in Tables 1 to 3 below.

[Agglomerate particle size distribution]
In each conductive composition, aggregates of conductive agents such as carbon nanofibers and carbon black were observed using a particle size distribution analyzer LA500 (manufactured by Horiba, Ltd.). And the particle size distribution (%) of the aggregate of 10 micrometers or more was calculated | required.

[Crosslinking speed]
At 130 ° C., the time when the crosslinking torque was 90% (t90) and the time when the crosslinking torque was 10% (t10) were determined. And t90-t10 (minute) was made into the bridge | crosslinking speed | rate.

[Crosslinking rate delay rate]
The cross-linking rate (t1) of the conductive composition and the cross-linking rate (t2) of the composition before adding the carbon nanofiber (the comparative example product is a conductive agent such as carbon black) were determined. And the delay rate (%) of the bridge | crosslinking speed | rate was calculated | required from [(t1-t2) / t2] * 100.

[Electric resistance]
Each conductive composition is cross-linked under a predetermined condition (150 ° C. × 30 minutes) to produce a rubber sheet, or each conductive composition is coated on a glass plate to form a conductive coating film ( A thickness of 20 μm) was produced. And the electrical resistance (Rv1) of a rubber sheet or the like when a voltage of 1 V was applied in an environment of 20 ° C. × 50% RH was measured according to SRIS 2304. Moreover, the electrical resistance (Rv2) when the rubber sheet or the like was stretched by 100% was measured according to SRIS 2304. Then, the number of variable digits was obtained from log (Rv2 / Rv1).

[Hardness (JIS type A)]
Each conductive composition is cross-linked under a predetermined condition (150 ° C. × 30 minutes) to produce a rubber sheet, or each conductive composition is coated on a glass plate to form a conductive coating film ( A thickness of 20 μm) was produced. And hardness A of this rubber sheet etc. was measured according to JIS K 6253. A rubber sheet or the like was prepared in the same manner as described above using the composition before the addition of carbon nanofibers (comparative product is a conductive agent such as carbon black). The hardness B of the rubber sheet was The measurement was performed in the same manner. The hardness variation rate (%) was determined from [(hardness A−hardness B) / hardness B] × 100.

[Elastic modulus]
Each conductive composition is cross-linked under a predetermined condition (150 ° C. × 30 minutes) to produce a rubber sheet, or each conductive composition is coated on a glass plate to form a conductive coating film ( A thickness of 20 μm) was produced. And the elastic modulus A of this rubber sheet etc. was measured according to JISK7161. Further, a rubber sheet or the like was prepared in the same manner as described above using the composition before the addition of carbon nanofibers (the comparative example product is a conductive agent such as carbon black). Measured in the same manner as above. Then, the elastic modulus variation rate (%) was determined from [(elastic modulus A−elastic modulus B) / elastic modulus B] × 100.

[Compression set (permanent elongation)]
Each conductive composition was crosslinked under predetermined conditions (150 ° C. × 30 minutes) to prepare a rubber sheet. The compression set of the rubber sheet was measured according to JIS K 6262 under the conditions of a temperature of 70 ° C., a test time of 22 hours, and a compression rate of 25%. In addition, about the thing which cannot produce a rubber sheet, 25% extending | stretching was performed and the permanent elongation was measured according to JISK6254.

  From the above results, all of the examples had a small particle size distribution of aggregates, a high crosslinking rate, and a low rate of crosslinking rate.

  In contrast, the comparative product corresponded to at least one of a large aggregate particle size distribution, a low crosslinking rate, a large fluctuation in electrical resistance, and a large delay rate of the crosslinking rate.

  Next, using the conductive composition, a developing roll was produced as follows.

  First, a conductive composition was prepared in the same manner as in Example 1. The conductive composition is poured into an injection mold having a shaft (core 10 mm, made of SUS304) and heated under conditions of 150 ° C. × 45 minutes, and then demolded. Then, a developing roll in which a base layer (thickness 4 mm) was formed along the outer peripheral surface of the shaft body was produced.

  A conductive composition was prepared in the same manner as in Example 2. And the developing roll was produced like Example 14 except forming a base layer using this.

  A conductive composition was prepared in the same manner as in Example 3. And the developing roll was produced like Example 14 except forming a base layer using this.

  A conductive composition was prepared in the same manner as in Example 4. And the developing roll was produced like Example 14 except forming a base layer using this.

  A conductive composition was prepared in the same manner as in Example 5. And the developing roll was produced like Example 14 except forming a base layer using this.

  A conductive composition was prepared in the same manner as in Example 6. And the developing roll was produced like Example 14 except forming a base layer using this.

  A conductive composition was prepared in the same manner as in Example 7. And the developing roll was produced like Example 14 except forming a base layer using this.

  A conductive composition was prepared in the same manner as in Example 8. And the developing roll was produced like Example 14 except forming a base layer using this.

  A conductive composition was prepared in the same manner as in Example 9. And the developing roll was produced like Example 14 except forming a base layer using this.

[Comparative Example 8]
A conductive composition was prepared in the same manner as in Comparative Example 1. And the developing roll was produced like Example 14 except forming a base layer using this.

[Comparative Example 9]
A conductive composition was prepared in the same manner as in Comparative Example 2. And the developing roll was produced like Example 14 except forming a base layer using this.

[Comparative Example 10]
A conductive composition was prepared in the same manner as in Comparative Example 3. And the developing roll was produced like Example 14 except forming a base layer using this.

[Comparative Example 11]
A conductive composition was prepared in the same manner as in Comparative Example 4. And the developing roll was produced like Example 14 except forming a base layer using this.

[Comparative Example 12]
A conductive composition was prepared in the same manner as in Comparative Example 5. And the developing roll was produced like Example 14 except forming a base layer using this.

[Comparative Example 13]
(Preparation of base layer material)
A conductive composition was prepared in the same manner as in Comparative Example 3.

(Preparation of surface layer material)
A conductive composition was prepared in the same manner as in Comparative Example 6.

(Preparation of developing roll)
The conductive composition is poured into an injection mold having a shaft core (diameter: 10 mm, made of SUS304), heated at 150 ° C. for 45 minutes, and then demolded. A base layer was formed along the outer peripheral surface of the shaft body. Next, the surface layer material was applied to the outer peripheral surface of the base rubber layer to form a surface layer. In this way, a developing roll having a base rubber layer (thickness 4 mm) formed on the outer peripheral surface of the shaft body and a surface layer (thickness 5 μm) formed on the outer peripheral surface was produced.

  Each characteristic was evaluated according to the following reference | standard using the developing roll of the Example goods and comparative example goods which were obtained in this way. These results are shown in Table 4 and Table 5 below.

[Electric resistance]
The median value and variation digits (36 points) of each developing roll were measured according to SRIS 2304 using a 1 mm ² electrode at a voltage of 1V.

[Hardness (JIS type A)]
The hardness of each developing roll was measured according to JIS K 6253.

(Compression set)
The compression set of each developing roll was measured according to JIS K 6301 under conditions of a temperature of 70 ° C., a test time of 22 hours, and a compression rate of 25%.

(Development characteristics)
(Image unevenness)
Each developing roll was incorporated into a commercially available color printer and image evaluation was performed. In the evaluation, a case where there was no density unevenness in a halftone image and no thin line breaks or color misregistration was given as ◯, and a case where it was not, was given as x.

(Pressure contact mark)
Each developing roll was incorporated in a commercially available color printer and image evaluation was performed, and then the pressure contact trace on the developing roll surface was visually observed. In the evaluation, the case where there was no pressure contact mark was indicated by ◯, and the case where there was a pressure contact mark was indicated by ×.

  From the results in the above table, all of the development rolls of the examples had small variations in electrical resistance, low hardness, small compression set, and excellent development characteristics.

  On the other hand, the developing roll of the comparative product corresponds to at least one of large variation in electrical resistance, high hardness, and large compression set, and has poor development characteristics.

  Next, using the conductive composition, a charging roll was produced as follows.

  First, a conductive composition was prepared in the same manner as in Example 11. The conductive composition is poured into an injection mold having a shaft (core 10 mm, made of SUS304) and heated under conditions of 150 ° C. × 45 minutes, and then demolded. Thus, a charging roll in which a base layer (thickness 3 mm) was formed along the outer peripheral surface of the shaft body was produced.

  A conductive composition was prepared in the same manner as in Example 12. And the charging roll was produced like Example 23 except forming a base layer using this.

[Comparative Example 14]
A conductive composition was prepared in the same manner as in Comparative Example 3. And the charging roll was produced like Example 23 except forming a base layer using this.

[Comparative Example 15]
(Preparation of base layer material)
A conductive composition was prepared in the same manner as in Comparative Example 3.

(Preparation of surface layer material)
A conductive composition was prepared in the same manner as in Comparative Example 6.

(Preparation of charging roll)
The conductive composition is poured into an injection mold having a shaft core (diameter: 10 mm, made of SUS304), heated at 150 ° C. for 45 minutes, and then demolded. A base layer was formed along the outer peripheral surface of the shaft body. Next, the surface layer material was applied to the outer peripheral surface of the base rubber layer to form a surface layer. Thus, a charging roll having a base rubber layer (thickness 3 mm) formed on the outer peripheral surface of the shaft body and a surface layer (thickness 5 μm) formed on the outer peripheral surface was produced.

  Using the charging rolls of Examples and Comparative Examples thus obtained, each characteristic was evaluated in accordance with the developing roll evaluation method described above. These results are also shown in Table 6 below.

  From the results shown in the above table, all of the charging rolls of the examples had small variations in electrical resistance, small compression set, and excellent charging characteristics.

  On the other hand, the charging roll of the comparative example product had a large variation in electrical resistance, a large compression set, and poor charging characteristics.

  Next, using the conductive composition, a transfer belt was produced as follows.

[Preparation of base layer material]
A conductive composition was prepared by dispersing 10 parts of Ketjen Black EC (Ketjen Black International Co., Ltd.) in 100 parts of polyamideimide resin (Toyobo Co., Ltd., Viromax HR16NN).

(Preparation of surface layer material)
A conductive composition was prepared in the same manner as in Example 13.

[Production of transfer belt]
A transfer belt having a two-layer structure in which a surface layer (thickness: 5 μm) was formed on the surface of the base layer (thickness: 200 μm) was produced using the base layer material and the surface layer material.

[Comparative Example 16]
In the same manner as in Comparative Example 7, a conductive composition serving as a surface layer material was prepared. A transfer belt was produced in the same manner as in Example 25 except that a surface layer was formed using this conductive composition.

  Using the transfer belts of Examples and Comparative Examples thus obtained, each characteristic was evaluated in accordance with the above-described developing roll evaluation method. These results are also shown in Table 7 below.

  From the results in the above table, the transfer belt of the example product had small variations in electrical resistance and excellent transfer characteristics.

  On the other hand, the transfer belt of the comparative example product had a large variation in electric resistance and was inferior in transfer characteristics.

  The conductive composition for an electrophotographic apparatus obtained by the production method of the present invention includes, for example, a roll such as a developing roll, a charging roll, a transfer roll, a fixing roll, a toner supply roll, a static elimination roll, a paper feed roll, a transport roll, and a cleaning roll. It is used for electrophotographic equipment members such as members, developing blades, blade members such as charging blades and cleaning blades, belt members such as transfer belts and paper feed belts.

Claims (5)

0.2 to 3 parts by weight of the following (B) is blended with respect to 100 parts by weight of the following (A), the following (B) is predispersed in the following (A), and the above (B) is after if Shin loosen multiple aggregated formed by aggregates, preparation of the pre-dispersed (a) and (B) and the electrophotographic apparatus for conductive composition characterized in that it comprises a step of kneading.
(A) A liquid polymer having a viscosity of 10,000 to 80,000 mPa · s (25 ° C.) .
(B) Carbon nanotubes having a diameter of 1 to 50 nm .   The liquid polymer of (A) is liquid silicone rubber, liquid polyoxyalkylene rubber, liquid polyisobutylene rubber, liquid butadiene rubber, liquid isoprene rubber, liquid styrene-butadiene rubber, liquid ethylene-propylene-diene terpolymer rubber. And the method for producing a conductive composition for an electrophotographic apparatus according to claim 1, which is at least one selected from the group consisting of a binder for ultraviolet crosslinking. A method according to claim 1 or 2, an electrophotographic apparatus for electrically conducting composition described you predispersed using a bead mill. The method for producing a conductive composition for an electrophotographic apparatus according to any one of claims 1 to 3, wherein the following (C) is further added and kneaded to the predispersed (A) and (B).
(C) At least one selected from the group consisting of a crosslinking agent, a reaction retarding agent, a catalyst, and a photoinitiator. The method for producing a conductive composition for an electrophotographic apparatus according to any one of claims 1 to 4 , further comprising a crosslinking step after the step of kneading (A) and (B).